// Author: combacsa@kaist.ac.kr
// http://www.jungol.co.kr/prog/Hanal/hanalView.php?qs_code=129

//#define COMPILE
// 노가다 굿/
#ifdef COMPILE

#include <fstream>
#include <iomanip>
using namespace std;

double round(double x) {
	return (double)(int)(x * 10 + 0.5) / 10.0;
}

int main() {
	ifstream in("input.txt");
	ofstream out("output.txt");
	char y;
	do {
		out << "밑변의 길이 = ";
		int a, b;
		in >> a;
		out << "높이 = ";
		in >> b;
		out << "입력한 삼각형의 넓이는 " << fixed << setprecision(1) << round((double)(a) * (double)(b) / 2.0) << "입니다." << endl;
		out << "계속하시겠습니까? ";
		in >> y;
	} while ((y == 'y') || (y == 'Y'));
	out.close();
	in.close();

	return 0;
}
#endif
